Fig. 1.

Cat-S stimulates ENaC currents in Xenopus laevis oocytes expressing human ENaC. a–d Oocytes expressing human ENaC were incubated for 30 min in protease-free solution (control) or in a solution containing either Cat-S (1 μM) or chymotrypsin (2 μg/ml). Amiloride-sensitive whole-cell currents (ΔI _ami) were determined before (−) and after (+) incubation. Six representative whole-cell current traces from one batch of oocytes are shown. a–c Amiloride (ami) was present in the bath solution to specifically inhibit ENaC as indicated by black bars. d Individual ΔI _ami values from a representative experiment using one batch of oocytes. Data points obtained from an individual oocyte are connected by a line